Improvement of Characteristics of Roller Compacted Concrete by Classified Fly Ash
T. Fukute, K. Nakano, and M. Ishll
Appears on pages(s):
compacting; compaction tests; fly ash; particle size distribution; pavements; roller compacted concrete; Materials Research
Classified fly ash (CFA) is produced by separating the fine components of fly ash by means of air classification. CFA is made of fine particles of micro-meter size and spherical shape and is expected to improve the consistency of fresh concrete and the durability of hardened concrete. The use of CFA in roller compacted concrete (RCC) pavement has the effect of reducing the water content of RCC mixtures and, therefore, the drying shrinkage and number of joints in pavement. RCC pavements have become popular for roads and streets in Japan. The maximum thickness of RCC slabs that may be placed in one layer is limited to 25 cm, because of limitations in the compactibility of the concrete and control of the pavement surface profile. To increase the slab thickness of RCC placeable in one layer, an improved concrete that requires minimal energy for obtaining a high filled-volume ratio is desirable. In this paper, the effects of CFA additions to cement on compactibility and water content of RCC mixture were studied.